1. Field of the Invention
Aspects of the present invention generally relate to an image forming apparatus having a sheet stacking apparatus that stacks sheets, a control method for the image forming apparatus, and a storage medium.
2. Description of the Related Art
The variation in image forming apparatuses advances, and an image forming apparatus is used to connect a large number of apparatuses, such as a sheet stacking apparatus for feeding or discharging a sheet or a finishing apparatus, to the image forming apparatus for cooperation.
A sheet stacking apparatus for discharging a printed sheet has, as an accessory, an elevating tray or a carriage to carry a large amount of sheets. The elevating tray is usually moved up to stack the printed sheets. However, the elevating tray needs to be mechanically moved down to extract the sheet from the sheet stacking apparatus.
Therefore, if a power supply of the sheet stacking apparatus is turned off while the elevating tray is moved up, the power supply needs to be turned on again so that the elevating tray is moved down to extract the sheet remaining in the sheet stacking apparatus.
A sheet stacking apparatus that feeds a sheet before printing includes an open button to open the sheet stacking apparatus. When detecting that the open button is pressed, the sheet stacking apparatus is mechanically opened. Therefore, if the power supply of the sheet stacking apparatus is turned off in a normal state, the power supply then needs to be turned on again and the open button of the sheet stacking apparatus needs to be pressed to extract the sheet remaining in the sheet stacking apparatus.
Japanese Patent Application Laid-Open No. 2009-35826 discusses a sheet stacking apparatus in which an elevating tray is moved down when a power supply of the apparatus is turned off to extract the sheet from the apparatus. In the sheet stacking apparatus discussed in Japanese Patent Application Laid-Open No. 2009-35826, the elevating tray is also moved down when the power supply is turned off, and the sheet can be thus extracted.
However, in the sheet stacking apparatus discussed in Japanese Patent Application Laid-Open No. 2009-35826, the elevating tray is always moved down without a consideration of a case where there are not any sheets in the sheet stacking apparatus when the power supply is turned off. Therefore, an unnecessary time is required so that the elevating tray is moved up when the power supply is turned on again.
The above operation is not addressed when the sheet is not extracted with a configuration of the feeding sheet stacking apparatus when the power supply is turned off.